Lowest temperature in Hong Kong on July 31?

Platform comparison

Market context

Polymarket has this contract at **3% YES** today, implying traders think Hong Kong’s lowest temperature on 31 July will land in the relevant range only rarely. The market settles on the Hong Kong Observatory’s final **“Absolute Daily Min (deg. C)”** for that date, so the only number that matters is the published minimum temperature in Celsius to one decimal place, not the forecast range or any intraday reading from elsewhere.[17][13]

For context, Hong Kong’s July climatology is typically hot and humid: the Observatory’s 1991–2020 normals put the average July minimum around **26.9–27.0°C**, with late-July values close to that level rather than anything exceptional.[6] The city can, however, produce brief cool dips when rain or thunderstorms pass through, and the Observatory’s July 2023 summary noted showery weather in the small hours of 31 July before conditions improved later in the day.[8] For Polymarket users holding the position on Polygon, the contract’s conditional tokens simply track where the final HKO print will fall once the Daily Extract is published and the settlement window can close.[17]

Traders should watch the Observatory’s timetable for the Daily Extract, because this market cannot resolve until the final climate data for 31 July 2026 is posted on the HKO climatology page.[17] The main catalyst is therefore not a policy announcement but the timing of the official publication and any late-day weather change in Hong Kong that shifts the overnight minimum before the HKO’s final daily figure is fixed. Near-term weather data from the Observatory’s own current and historical pages, together with any late shower or thunderstorm coverage in the local press, are the most relevant inputs for pricing the last few hours of this market.[9][3]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

FAQ

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.